But both sides have chosen the same weapons: Jackson himself, his problems with drugs and the wrenching details of his last days. What’s most surprising is that even with so much written and revealed about Jackson since his death four years ago, there is still more to learn.

Martin S. Putnam, A.E.G.’s lead lawyer, promised in his opening statement that the case would reveal “ugly stuff” about Jackson’s private life. And witnesses called by lawyers for Jackson’s 83-year-old mother, Katherine, have testified at length about Jackson’s addiction to medications, his physical deterioration and his belief that he was talking to God.

The case hinges on the fairly limited questions of whether A.E.G. hired Dr. Conrad Murray, the physician who administered the powerful anesthetic that killed Jackson in June 2009, and if it was negligent in doing so. Dr. Murray was convicted of involuntary manslaughter in a separate criminal trial in 2011, and is serving a four-year prison sentence.

Lawyers for Mrs. Jackson have said that they may seek up to $5 billion in damages. But the greater risk for both A.E.G. and the Jackson family is the potential damage to their reputations as the details of Jackson’s life and final days are revealed, in perhaps even greater detail than at Dr. Murray’s criminal trial.

“It’s all downside for A.E.G.,” said Bill Werde, the editorial director of Billboard magazine. “And this trial affects A.E.G., as well as the touring and broader music industry. Every time people see headlines about these incredibly sad details of Michael Jackson’s life, it makes this seem to be an uncaring business that exploits stars, even to their peril.”

Witnesses last week included two women who had worked for Jackson for decades, both describing him as a sensitive artistic genius haunted by physical pain. One, Karen Faye, his makeup artist since the early 1980s, said that Jackson became more dependent on prescription drugs over the course of his career.

The other woman, the choreographer Alif Sankey, tearfully recounted how, less than a week before Jackson died, she had begged Kenny Ortega, the director of “This Is It,” Jackson’s attempted comeback concerts, to take him to the hospital after Jackson appeared ill and said that God was speaking to him.

“I had a very strong feeling that Michael was dying,” Ms. Sankey said. As she testified, the only other sound audible in the small courtroom was the tapping of journalists on their laptops.

On Monday another choreographer on “This Is It,” Stacy Walker, who was called by lawyers for A.E.G., testified that she saw no signs that Jackson was in bad shape before he died.

“I just never in a million years thought he would leave us, or pass away,” Ms. Walker said, according to a report by The Associated Press.

The evidence in the case has included e-mails from A.E.G. executives which the Jackson lawyers say show that the company was acting as Dr. Murray’s employer. One message, sent to Mr. Ortega less than two weeks before Jackson’s death, says of Dr. Murray: “We want to remind him that it is A.E.G., not M. J., who is paying his salary. We want to remind him what is expected of him.”

A.E.G., a global sports and entertainment company controlled by the billionaire Philip F. Anschutz, denies that it hired Dr. Murray, saying that he had been selected by Jackson and that his $150,000-a-month salary was to come out of Jackson’s earnings for the tour.

What damage the case could cost Jackson’s reputation — and his valuable estate — is unclear. The estate has flourished, even though his faults and indiscretions have already been widely publicized, and entertainment and estate experts say that the details revealed in this trial are likely to elicit more sympathy for Jackson, not less.

Article source: http://www.nytimes.com/2013/05/15/business/media/at-michael-jackson-trial-question-of-aegs-negligence.html?partner=rss&emc=rss